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What you need to know about signing up for Medicare at age 65

Older woman getting her medicare eligibility letter

Learn all about how your Medicare options can keep you healthy.

Happy early birthday! You’re going to be turning 65 soon. And that means it’s time to start thinking about Medicare.

First, it’s a good idea to understand the basics. Medicare is a health care program run by the government. It provides benefits for adults ages 65 and older. It also covers some people with disabilities and end-stage kidney disease. (The kidney is an organ that filters blood.)

Signing up for Medicare can sometimes be a little confusing. There are a lot of facts and figures to take in. But with a little help, you can be well on your way to success.

Here’s a crash course on what Medicare is and how it works.

A guide to the parts of Medicare

The first thing to know about Medicare is that it normally comes in four parts. Each one covers different types of health care services:

  • Part A covers hospital services and care.
  • Part B covers doctor visits and care that doesn’t involve spending a night in the hospital.
  • Part C is also called Medicare Advantage. You can choose this in place of Parts A and B. It often covers prescription drugs, dental, vision and hearing.
  • Part D covers prescription drugs and some vaccines.

You might see Medicare Parts A and B called Original Medicare. You get them through the U.S. government. Medicare Part C, on the other hand, is offered by private insurance companies. But that doesn’t mean fewer benefits. Medicare must approve Medicare Advantage plans.

If you have an existing health savings account, you can still use those funds to pay for eligible expenses. Use our tool to explore.

How to put Medicare’s parts together

Medicare follows a basic rule: The more parts of it you have, the more health care you get.

  • If you choose Original Medicare, you’ll get Medicare Parts A and B only. You can also add Part D, which gives you a prescription drug plan.
  • If you choose to go with Medicare Advantage, you get Parts A and B, plus prescription drug coverage. If you pick a plan that doesn’t include drug coverage, you can add a Part D to it.

Some parts of Medicare can be combined with a Medicare supplement health plan. You might also see it called Medigap. These plans cover some of your out-of-pocket costs that Parts A and B don’t cover. Those include things like:

  • Coinsurance: This is the percentage you pay for the cost of health services.
  • Copayment: This is a fixed amount you pay for health services.
  • Deductible: This is the amount you must pay for covered health care services before your insurance pays the rest.

In most states, Medigap plans are identified by the letters A through N. Every insurance company’s Medigap plans offer the same benefits to you.1

If you aren’t happy with the parts of Medicare you choose, you can change them. Medicare has an Annual Enrollment Period when you can make changes. It runs from October 15 to December 7. (Sometimes, you can make changes before this during a special enrollment period.) 

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What does Medicare cost?

What you pay for Medicare is all about what parts you choose and how much you use them. Your costs may include your monthly insurance bill, deductibles, copays and coinsurance.

This is what you’ll pay for Medicare in 2022:

  • Part A: If you or your spouse worked and paid Medicare taxes for at least 10 years, you will not pay a monthly bill. If you don't have that work history, you could pay up to $499 a month.
  • Part B: Most people will pay $170.10 a month, but if your income in 2020 was higher than $500,000, you could pay up to $578.30 per month.
  • Part C: Many Medicare Advantage plans have $0 or low-cost monthly insurance bills. But those monthly bills may be different based on where you live and your provider.
  • Part D and Medigap: Monthly bills and other costs differ based on your plan and provider.

You’ll also need to pay out-of-pocket costs when you get certain care. For example, with Medicare Part B, you must meet a $233 deductible in 2022 before Medicare starts paying. After that, Medicare typically pays 80% of your costs. You have to pay the remaining 20%.

If you have Medicare Advantage, how much you pay will be different depending on your plan. So you’ll want to look closely at your plan before enrolling.

Can you use your health savings account to pay for Medicare costs?

If you have a high-deductible health plan (HDHP), you may have a health savings account (HSA). An HDHP has a lower monthly insurance bill, but you’ll pay higher out-of-pocket costs for health care.

An HSA can help you pay for some Medicare costs. Normally, an HSA lets you save money, tax-free. But once you sign up for Medicare, you can no longer put additional tax-free money into your HSA. You can still use it to pay for monthly Medicare bills and other out-of-pocket expenses. Search eligible expenses with our tool. 

Is Medicare Advantage better for you?

If you’re still not sure what type of Medicare plan to choose, think about what you’re getting for your money. If you go with Original Medicare, you get Medicare Parts A and B. You’ll have to pay more for your Part D prescription drug plan and Medigap.

But if you go with Medicare Advantage, you may pay little to no monthly bill. That’s because some plans may pay part or all of your Part B bill. You’ll also get Medicare Parts A and B, plus a prescription drug plan, in many cases. And you can get added benefits like:

  • Adult daycare
  • Dental and vision benefits
  • Gym memberships
  • Hearing care and hearing aids
  • Home modifications
  • Meals
  • Transportation
  • Wellness programs

Remember that costs and coverage may vary among Medicare Advantage plans. These plans also tend to have set network of doctors. You’ll be able to check whether your doctor is in the network before you sign up. Always be sure to read the plan information carefully.

When can you sign up for Medicare?

The best time to sign up for Medicare is during your Initial Enrollment Period (IEP). This period lasts for seven months and includes the month you turn 65 plus the three months before and the three months after.

If you sign up before your birth month, your benefits will start the month you turn 65. If you don’t, it starts up to three months later. That could mean you might not have health insurance for a short period of time.

Can you delay enrolling in Medicare?

The answer is yes, but there’s a big “but.” You may be able to put off signing up for Medicare if:

  • You have insurance through a job and you plan to work past age 65.
  • You have insurance through your spouse’s job.

So what happens if you retire or lose your spouse’s insurance? You will get an eight-month Special Enrollment Period (SEP) to sign up for Medicare Parts A and B. During that time, you can also get Medicare Part D or go with Medicare Advantage. But you only have the first two months to do so without having to pay a penalty.

Can you sign up for Medicare at any other time?

You can also sign up for Medicare Part B during its General Enrollment Period (GEP). That runs from January 1 to March 31 each year. That’s only if you missed your IEP and didn't qualify for an SEP. Your benefits would start on July 1, so you might not have insurance for several months.

If you sign up for Medicare Part B during the GEP, you can then sign up for Medicare Advantage or Part D from April 1 to June 30. Once you have Medicare Part B, you can also sign up for a Medigap plan.

Can you change your Medicare plan?

You can make changes to your Medicare plan without paying a penalty once a year. That happens during Medicare’s Annual Enrollment Period (AEP). It runs from October 15 to December 7 every year. During the AEP, you can join, switch or drop your Medicare Advantage or Part D plan. You can also return to Original Medicare.

If you’re already on a Medicare Advantage plan, you may have another chance to make changes. That happens during the Medicare Advantage Open Enrollment Period. It runs from January 1 to March 31 each year. During this time, you can switch your Medicare Advantage plan or switch back to Original Medicare. (You can’t switch from Original Medicare to a Medicare Advantage plan.)

What if you delay signing up for Medicare?

If you turn 65 and don’t sign up for Medicare on time, it could cost you more money. You might have to pay more per month for Medicare Part A, Part B and Part D. The rules are different for each, including what the penalty is, how long it lasts and how often you pay it.

  • For Medicare Part A (if you owe a monthly payment): You’ll pay an extra 10% for twice the number of years you delay enrollment.
    • Example: If you delay for two years, you’ll pay an extra 10% for four years.2
  • For Medicare Part B, you’ll pay an extra 10% for each 12-month period you delay enrollment. You’ll have to pay that extra fee forever.3
    • Example: If you delay for 24 months, you’ll pay an extra 20%.
  • For Medicare Part D, you’ll pay an extra 1% of your monthly bill for each month you delay signing up. You’ll have to pay that extra fee for as long as you have Part D.
    • Example: If you delay for 12 months, you’ll pay an extra 12%.4

Need help understanding your Medicare choices? Think about working with an insurance broker. And for more health tips you can trust, sign up for our health and wellness newsletter today. You’ll get insights backed by the Optum medical team delivered straight to your inbox.


  1. Medicare.gov. How to compare Medigap policies. Accessed June 26, 2022.
  2. Medicare.gov. Part A late enrollment penalty. Accessed July 12, 2022.
  3. Medicare.gov. What does Medicare cost? Accessed June 26, 2022.
  4. Medicare.gov. Part D late enrollment penalty. Accessed July 12, 2022.

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